The internal architecture of home personal computers (PC's) is virtually always based on a motherboard arrangement on which a CPU, memory module sockets, and various input/output (I/O) connectors are provided. The motherboard may be provided with a one or more expansion slots by which additional device boards can be connected to the computer, such as, for example, a sound board, a graphics board, etc.
The motherboard in a conventional PC is provided within a housing or cabinet that also typically includes a power supply and a cooling fan for cooling the interior of the housing.
In terms of its computing power and relatively compact overall size, the home PC is theoretically attractive for certain business applications, such unattended control of automatic bank teller machines (ATM's).
However, the motherboard-based PC architecture has several deficiencies that makes it unsuitable for reliable use in unattended applications.
First, the components in home PC's are relatively low quality and prone to failure. For example, the power supply in a home PC tends to have a high failure rate, usually because the overall system architecture does not provide sufficient cooling for the power supply. In part, the arrangement of components in a home PC tends to impede cooling air flow from the cooling fan. Therefore, the cooling process becomes less effective, and temperature sensitive components become prone to heat-related failure.
Indeed, home PC manufacturers are typically motivated to use relatively lower end components in order to maximize their profit margins. In some systems, the total cost of components might be several tens of dollars, while the system is sold to the consumer for several thousands of dollars. Moreover, home PC manufacturers frequently expect consumers to simply "buy up" to a new model when their current computer begins to fail. The monetary cost and inconvenience of repairing a home computer is at least perceived to be much more burdensome than simply buying a newer computer. Thus, home PC manufacturers are not terribly motivated to use unusually reliable components.
Consumers are also likely to buy up rather than spend time, money, and effort to upgrade an older computer. In particular, the motherboard arrangement of PC's are generally difficult to upgrade, requiring particular jumper settings, manipulation of parts within the restricted confines of the cabinet, and various system configuration setups that can be difficult to perform properly. In addition, vital parts of the computer system are provided on motherboard such that upgrading certain characteristics of the computer (e.g., upgrading the CPU beyond the range of clock speeds that the motherboard is physically designed to handle) requires replacing the entire motherboard. It can be appreciated that this effectively means completely replacing the entire computer.
Another factor that makes home PC's unsuitable for extended use in commercial applications is the relatively rapid turnover of system designs in the home PC market. A given home PC design is rarely produced for more than a year or so. Thus, the issue of spare parts and the like becomes difficult or impossible to resolve, since that given system will soon no longer be manufactured.
These factors make home PC's unsuitable for extended commercial use, particularly in an application where the computer is left unattended, for example, in an ATM.
A high rate of component failure is unacceptable because this requires frequent and costly and time consuming visits by skilled (and, therefore, expensive) repair technicians to various ATM sites. Once such failures occur, repair is made difficult due the motherboard configuration, because factors such as physical jumper settings and system configurations must be checked. Upgrading a conventional computer in an ATM is also troublesome because, again, an experienced technician must visit each ATM site. In a major metropolitan area, the number of sites that must be visited might well run into at least the hundreds, if not thousands. Moreover, once repair is required, it is certainly preferable to have a ready and reliable source of spare parts and the like in order to efficiently complete repairs. The above-mentioned fast turnover of home PC designs virtually mandates regular upgrades, even if only to maintain the ability to readily repair machines. Yet, this again raises the issue of the cost and inconvenience of sending experienced technicians to numerous sites.
In order to address the issue of system reliability, a computer system sometimes known as an Industrial Personal Computer (IPC) is conventionally available. IPC's are characteristically constructed for "heavy-duty" applications, and have increased tolerance for ambient operating temperature, humidity, shock loads, vibration loads, and particulate contaminants in the ambient atmosphere. Unfortunately, this increased operational performance is associated with a very high cost for system components, compared to home PC type systems. The sheer cost of the IPC's are economically prohibitive for certain commercial applications, such as ATM control, in view of the numbers of computer units required. In any event, in terms of protecting the investment in such a relatively expensive system, the IPC also requires service by an experienced technician in order to ensure that repairs and service are properly performed. Moreover, the internal architecture of IPC's are frequently based on the motherboard design. Therefore, the IPC suffers from the same problems as the home PC in terms of serviceability and upgradeability.